I am sorry for all the people having problems, but my Prusa mjni is finally just workjng and happily printing all the stuff I throw at it. Its been having issues here and there forever. I just figured out that the hotend has not been assembled correctly (heatbreaker to nozzle seal was weak) which became a greater issue when switching to a 0.25mm nozzle. Now after I fixed it, it is just awesome :)
I once designed a first prototype, and it worked so well I didn’t need the other 3 iterations I was planning.
It was a few years ago, but I’ll never forget (and probably never manage that again).